Method of bleaching.



xii 1&(3349658 EAHON Ut ltMlLLe on Home,

' ject of completelyremovin UNITED s'r 'rs Pa No Drawing.

To all whom it may concern:

Be it known that I, EnuARn- S'rEIonR, a:

citizen of the Re ublic of Switzerland siding at Villa K einberg No. 3', St. Gallen, Switzerland, have invented new and useful Improvements in Methods of Bleaching;

and I do hereby declare the following to be.

a full, clear, and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same.

This invention relates to a new and improved method of completely bleachingggt tg n and linen yarns, tissues,- e'mbroideries etc.

The improved method consists of a series of operatlons viz. a preliminary treatment by which the fats and oils and where necessary, the dressing are removed and the bleaching proper by a slightly acid bath of perman anate which is fol owed b removed. But when the. ware contains non- ,saponifiable fats, such as hydrocarbons, min-- eral oils or paraffins these are not dissolved and therefore remain in the merchandise wholly or partly. Such merchandise which n stances cons uenceof the action of the fatty matter w ichhas not been removed. This yelerfectly free from all fatty subiias a tendency toyellow later 'on m lowing may cause great dama for the value of a textile merchandise w ich is even only partly yellowed is considered to be v'er much reduced, 1 p

.Pi xtracting the fattysubstance has the oball fatty substances, also the non-saponi able ones, from the yarns, tissues and embroiderles to be a bath of soda an means for preventing ye lowing of the were through overbleachlng.

,oo MUWHUHM? KQE.

EDUARD STEIGEB, OF ST. GAIL-LEE, SWITZERLAND.

, i METHOD OF BLEACHING. 4

1,034,658, Specification of Letters Patent. Pajfiemi efl'Aug, 6, 1912,

Application filed January}, 1911. Serial No. 8013*.

l bleached and at the same time to obtain these fatty substances as byproducts. With this obyect in view the (yarns, tissues or embroideries are extracte with a solvent for fats and hydrocarbons in a suitable apparatus such as a Soxhlet siphon apparatus,

search iilll'llll andthus all fatty matter is'removed from them. As solvents for the fatt matter petroleum ether or benzin, chlori of ethylene, carbon tetrachlorid or mixtures of these extracting means may be employed. Cotton or linen merchandise which in the manner indicated has been carefully fatty matter may, after the dressing has been removed, be subjected to a bleaching process with the result that this process is freed from all much shorter than it was hitherto and thatthe tediousbucking process and'the use of soap are entirely done away with. This latter circumstance has the further advantag that the diiiiculties adhering to the use 0 lime soap for the bleaching are eliminated, for it is known that often yellowing is caused by lime soap remaining in the merchandise. r

The extraction of fatty matter has the following main advantages: It renders possible the removal of'fatty matter to any 'de sired degree in a short time and thus'pnevents yellowing through remaining fatty matter; it has the advantage thatno more consideration will have to be had of the na-x 'tureof the fats contained in the merchan dise- For example inthe case of embroiderles manufactured on. machines lubricated with mineral ()ll lb may occur-that someoll adheres to the were, As this oil is non saponifiable it remained in the were when the latter was bleached by the socailed English bleaching process, and the consequence was that the ware yellowed andwas spoiled into a solution as diastase which has a temperatirre of about 50 to 5 centigrade. This resume temperature must be maintained during the times, the merchandise will as a rule be comtreatment. Diestase changes the dressing pletcly bleached.

into a substance soluble in water. The, reao- The last step of the process has the obtion may be considered to be completed ject of removing the roducts of the decomwhen the ware does not show'a. blue tint position of cellulose {if any). At the same when touched. with a solution of iodin. time the bleaching is, so to speak, completed,

Then the m rcbundise is taken from the soand yellowing is prevented. For that purlution of ijlissirase and thoroughly washed. pose the bleached merchandise is heated in l stusc be prepared from brewery or an alkaline solution of a copper salt (Feb.-

10 distillery melt. in the form of an aqueous eX- ling solution diluted with'double its quantracl. 'nsg diastase for removing the tity of water) then the merchandise is re- \h'essiu cy rational, particularly when move to a solution of hydrochloric acid or c pian'liities have to be removed. This sulfuric acid, and finally '2. solution of soda.

p1. c inar step of the process is {01- is applied.

lowed by the bleaching process proper by Merchandise cotton and. linen yarns, tiswhich operation the coloring matter is desues, embroideries, etc., are not iii-danger of so stroycd, greatest possible care being being yellowed by fatty matters remaining taken of the fibers and the cellulose forming in them. them. Having now particularly described and so The merchandise free from fat and dressa certained the nature of the said invention ing is treated for about. two minutes with u add in what manner the same is to be perslightly ucid water solution of permangamed, I declare that what I claim is:

.uzuc at the ordinary air temperature. 1.. The process of treating textiles com- Acetic acid preferably used. Permangaprising a preliminary treatment for removnutes have been previously used for bleaching the fat, bleaching chiefly with permancannot be used without diiliganate, then subjecting the product to W ron because cotton and jute rehot soda bath, washing it, and then finishltis desirable to use'pering by treating it with an alkaline solution auate for cotton also because it bleaches of copper salt, a solution of an acid, and

" thereafter with a solution of soda, substan- -;'i.i'ter treating; the material to be bleached tially as described.

with a diutcd and slightly acid solution of 2. The process of treating textiles, comperma use it is washed in water and prising a preliminary treatment for removthe mung lQSt (llOXlCl deposited on the fiber mg the fat by means of a solvent for fats 3 3 remo .i by treatment with sulfurous and hydrocarbons to prevent yellowing by acid or pcroxiid of hydrogen. lVhen sulfurany remaining fatty matter, bleaching 10 nus acid employed its concentration chiefly with permanganate-then subjecting should be about 1 to 2 B. This treatment the product to the action of ahot soda bath, is it'ollou'ed by a treatment with reagents washingit, and finishing by treating it with so having: 1'. hydrating and at the same time an alkaline solution oi a copper salt, a solutlissol'vinp; action on the products of decomtion of an acid, and thereafter with a solu- 1( I rt the cellulose (if these are prestion of soda, substantially as described.

cut). Such reagents are acid lyes, but these 3. The process of treating textiles comwoulrl duumc the fiber because the cellulose prising a preliminary treatment for remov- 45 of it would. be too much affected and the ing the fat from the textile product by strength of the fiber reduced. To overcome means of a solvent for fats and hydrocar- 11 this drswbuclq. that is to lastingly bleach bons for the purpose of preventing yellowthe natural coloring; matter of the cotton ing by any remaining fatty matter, a treatwithout diuuaging the fiber a diluted hot ment with a slightly diluted acid bath of to solution of soda is employed the concentrapermanganate, removing any dioxid of mantion of which is preferably 1 B6. The gancse deposited on the fiber, subjecting the 1 treatment in the soda bath can be effected textile to a hot alkaline bath and to a finishwith or without pressure. The soda bath ing treatment with an alkaline solution of may also wih advantage be used immedia copper salt, a solution of an acid, and nicly after the treatment with pcrmangathereafter with a solution of soda, substannatc and washing with water instead of at tially as described. 1

the end of the .ics treatment. In this case 4. The process of bleaching textiles, comthe dissolving client on. the products of prising a preliminary treatment for remov- "ion of the cellulose is particuing the fat from the textile product by c.

co iand. Obviously a bath of potash solvent for fats and hydrocarbons, a treatthe c. me effect as a soda bath. ment with a diluted, slightly acid solution 1 The bl curbing; operations proper must be of permanganate; removing the superoxicl repeated :everul times in the succession dedeposited on the fiber, then treating the tenz-icribcd. After having been treated four tile with a hot bath of an alkali, and subjecting the textil to a finishing treatment, comasl my imventioml have signed my name in prising heating the textile in an alkaline presence 0f (zwo subscribing witnafies. solution of a copper salt, removing any re- -maining copper compounds with a sn'lution 5 of an acid and then treating the textile with Witnesses:

21- 801126921 of soda, substantmily as (iescribed. ERNST FISCHER, In testimony that I clnim the foregoing CARL GUBLER.

EDWARD smmnn 

